Edward j



(No Model.)

E. J. HARDY.

AIR PUMP.

Patented Oct. l, 1895.

.lnllllllnlllllqllvllrlllllln vLuevLCo/a @311k ,12in/s forumj @y 777/rxlfsam/ Mib/ML ma@ ANDREW EGRANAM. PNOT-LITHQWASKLNGTOMD D time STnTns PATENT 'Trina EDWARD J. HARDY, OF BROOKLYN, NE7l YORK, ASSIGNOR TO THE HARDY ICE MACHINE COMPANY, OF SAME PLACE.

AIR=PUIV1P.

SPECIFICATION forming part of Letters Patent No. 547,012, dated October 1, 1895. Application filed January 28, 1891. Serial No. 379,384. (No model.)

.To all whom it may concern:

Be it known that I, EDWARD J. HARDY, a citizen of Great Britain, residing at Brooklyn, in the county of Kings, State of New York, have invented certain new and useful Improvements in Air-Pumps, of which the following is a specification, reference being had therein to the accompanying drawings.

My invention relates to air or Vacuum pumps in which a substantially non-volatile liquid is used to seal the valves and pistons to facilitate their operation; and the objects of my improvement are to produce a simple and inexpensive device of this class having its movable parts liquid-sealed, as will be hereinafter described, and specifically set forth in the claim. I attain these objects by the construction illustrated inthe accompanying drawings, in which- Figure 1 is a longitudinal vertical section of an air-pumping apparatus constructed in accordance with my invention. Fig. 2 is a longitudinal vertical section of a modification of the same.

This invention is an improvement on the pump shown in Patent No. 446,205, granted to me February 10, 1891.

In the present construction, (shown in Fig. 1,) A represents a cylinder or pump-barrel, Which at the beginning of the operation is to be nearly filled with a substantially non-volatile liquid-as oil, mercury, or sulphuric acid-admitted preferably through the pipe A2, projecting upward from the cover of the cylinder, While the valve K in said pipe is temporarily lifted by the operator. Within said cylinder is placed a hollow piston B, having in its concaved bottom an opening closed by an upwardly-lifting valve O, the stem C2 of which has its upper end guided in a recess in the lower end of the piston-rod B2, and a spring C3 coiled upon said stem has one end bearing against the lower end of the pistonrod, while the opposite end bears upon the valve and normally keeps it upon its seat. The top of the piston B has openings Z) therein, through which the air and liquid received therein through the bottom can escape into the upper portion of the cylinder A.

O11 the side ofthe pump-cylinder A is placed a smaller cylinder E, having its upper end connected by port or pipe D and its lower end by a port or pipe H with said cylinder A. i/Vithin the cylinder E is placed a solid piston F, which divides the interior of said cylinder into two chambers, which are either closed to each other or connected with each other, according to the location occupied by the pistou F, as there is a port or pipe G in the side or wall of the cylinder, which pipe has its upper opening in the top chamber and its lower opening in the bottom chamber, and the pistou is adapted to close said lower opening. The piston F is forced down, preferably bya springf, coiled upon the piston-rod F2, one end of said spring bearing upon a collarfz, secured to said rod, andthe other end bearing against an arm lm, projecting from the side of the frame M. The piston F is elevated by means of a pin or cam on the crank-shaft N, engaging with or under a projection on the upper end of the piston-rod F2; but other well-known means may be used to reciprocate the pistou at a proper time relatively to the position occupied by the hollow piston B. In the position shown in Fig. 1 the piston F is represented at substantially the upper end of its stroke. At this point the liquid above the piston F passes through the port G into the lower part of the cylinder E below the piston, remaining there until the piston Bis on its upward stroke. A small portion of the liquid then escapes through the pipe H and lubricates the sides of said piston B. When the latter is at the end of its upward stroke its bottom has passed abo-ve the port or pipe H and opened it. At that moment the piston F, actuated either by its operative cam or by the spring f, descends to the bottom of the cylinder E and forces the liquid therein through the pipe H into the cylinder A below the piston B. At the same time the air to be exhausted from the vessel I2 or any other vessel passes through the pipe l into the cylinder A under the pistou B. During the upper stroke of this hollow piston a portion of the liquid above it passes through the pipe D into the cylinder E to continue the operation above described, and a small portion is splashed against and around the valve K and lubricates it, and the air compressed above the piston B escapes through the pipe A2. To

IOO

release the pipe A2 of liquid in case it should accumulate therein a pipe L may have one end inserted in the side thereof and the opposite end made to enter the top of the cylinder E; but said pipe L is normally closed by a cock l, which is opened only occasionally to relieve the pipe A2 of liquid.

In the modification shown in Fig. 2 cylindcrs A and E are used; but the connectingpipe D of Fig. l is dispensed with, and also the port G and the piston F of the small cylinder; but the top of the cylinder E is connected with the discharge-pipe A2 by the pipe L, and the pipe H, uniting the cylinders A and E, is contracted or controlled by a cock 7L, by which its area can be regulated, so as to admit only a small amount of liquid into the cylinder A, corresponding with the amount expelled therefrom past the upper valve K;- but by the arrangement shown in Fig. l a determined amount of liquid is forced into the cylinder A by the piston F, in accordance with its stroke and the area of the bottom of the cylinder E.

Having now fully described my invention, I claim- The combination in an air pumping apparatus of a pump cylinder having au air inlet in the side and a valve in the top thereof and a piston B therein having an upwardly lifting valve with a cylinder E having its top and bottom connected by pipes with the cylinder A, a piston F in the cylinder E and a port or pipe G in the side of said cylinder E, said pipe G connecting the chambers above and under the piston F, substantially as described.

In testimony whereof I aflix my signature in presence of two Witnesses.

EDWARD J. HARDY.

Witnesses:

JOSEPH M. KEANE, N. R. COTTMAN. 

